1. Field of the Invention
The present invention generally relates to an electrical connector, and more particularly to an electrical connector for removable mounting a chip module to a printed circuit board.
2. Description of Related Art
Connectors for mounting a chip module, such as a Central Processing Unit (CPU), to a printed circuit board are widely used in electrical equipments. Such a connector usually includes a base, a plurality of contacts retained in the base, a fastening frame partially surrounding the housing, a metal clip and an operational lever attached to the fastening frame. The base has a mounting surface to which the chip module is mounted and a connecting surface attached to the printed circuit board.
U.S. Pat. No. 7,001,197 issued to Shirai on Feb. 21, 2006 typically discloses another type of connector socket, and which can be generally called LGA socket. As clearly shown in Figures, the socket generally includes a metal stiffener with a housing securely supported therein. Then a metal clip is pivotally assembled to the stiffener. On the other hand, a clip is pivotally assembled to the other side of the stiffener and when the clip is closed to the stiffener, the lever having a cam can lock the clip to a closed position. By this arrangement, if before the clip is closed, and a CPU is seated on the housing, then the clip will tightly press the CPU toward the housing ensuring proper electrical connection therebetween.
Two opposite edges of the base respectively upward extend to form a mounting portion for pivotally mounting the metal clip and a receiving portion for pivotally receiving the lever. The metal clip is provided with an engaging tab adjacent to the receiving portion of the base for locking with the lever. When mounting, the connector is mounted to the printed circuit board, then the chip module is assembled to the mounting surface of the base and the metal clip is rotatably to partially cover the chip module, finally rotating the operational lever to a closed position for pushing the chip module against the base. The contacts retained in the base facilitate the electrical connection between the chip module and the printed circuit board.
However, the connector with above structures has at least the shortcomings as follows: When rotating the lever to close the metal clip, the lever effect a resultant force on the engaging tab of the metal clip, and the resultant force can be resolved into a horizontal force and a vertical force acted on the tab. The horizontal force pushes the tab to move towards the mounting portion of the base whereby the lever disengages from the tab. Therefore, the metal clip couldn't lock with the lever smoothly.
Therefore, it is desired to provide an improved electrical connector to stress the problems mentioned above.